Brace for excavations



- (No Mo'del 2 Sheets-Sheet 1.

' w. J. DUNN. BRAGE FOR EXOAVATIONS.

Patented July 8 HAIHM W 1V: i A V r w w W W V M K "$1 W WITNESSES 2 Sheets-Sheet 2.

(No Model.)

w. J DUNN. BRAOE FOR EXGAVATIONS.

IN My]? Patented July 8, 1890.

UNITED STATES PATENT OFFICE.

IVILLIAM J. DUN N OF EMSYVORTH, PENNSYLVANIA.-

BRACE FOR EXCAVATIONS.

SPECIFICATION forming part of Letters Patent m5. 431,689, dated July 8, 1890.

Application filed March 15,

To all whom it may conceive:

Be it known that I, VILLIAM'J. DUNN, a

. citizen of the United States, residing at Ems I ponent parts.

worth, in the county of Allegheny and State of Pennsylvania, have invented and produced a new and useful Improvement in Braces for Excavations; and I do .declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming a part thereof, in which like letters indicate like parts.

My invention relates to improvements in extensible braces for holding the side walls of earth excavations, in which the extension is secured by a screw working in a hollow sleeve and operated by a handled nut; and the objects of my improvements are, first, to provide a radial adjustment in any direction at both ends of the brace where it engages in the shoes, so as to allow of easy and accurate placing of the brace and the relief of the screw in the sleeve from strain caused by the unequal angles whichthe base of the shoes in practice are obliged to assume; second, to form the base of the shoe so that it will secure a firm hold upon the plank lining on which it rests, and thus prevent all danger of slip or displacement, and, third, to so connect the shoes to the screw and to the sleeve that they will not lose their position inhandling and will resist the twisting strain caused by working the nut. I attain these objects by the mechanism illustrated in the drawings, in which 7 Figure 1 is an elevation of the entire apparatus as it appears in position in the excavation. Fig. 2 is a sectional view of the com- Fig. 3 is a view of the face of the shoe that engages the siding. Fig. 4 is a top view of the socket side of the shoe. Fig. 5 is a top view of the cap or connecting piece of the shoe, and Fig. 6 is an end view of the ball which works in the socket.

In the sectional view,Fig. 2,A is the screws'tem, of malleable iron, cast hollow to lighten and strengthen it, and having the ball B at one end. This ball is provided with two square projecting lugs b b, Fig. 6.

O C are the shoes, having a socket D, Fig. 4, to receive the ball B, and provided with re- 1890. SerialN0. 344,052. (No model.)

cesses cl d' 'to receive the lugs 19' I). These recesses are much larger than the lugs to allow for freeplay and adjustment.

E is the cap, which passes freely over A, and is secured by the rivets c e to the shoe 0, thus making it a permanent attachment to the ball B, while allowing free adjustment in any direction. The face of the shoe C, Fig. 3, is hollowed out to lighten and strengthen it and to sharpen the edges of a a, a, which, when the strain of the screw is put upon them, enter into the surface of the plank lining and form a secure hold against displacement, and the lugs 12' b, striking the walls of the recesses d d, prevent any twisting or revolving of the other parts that would result from working the nut F.

G is the sleeve, covering the screw-stem A. It is made of any desired length. Its outer end is provided with a'ball the same as the screw-stem. In this case it enters smoothly the internal diameter of the sleeve, and is secured thereto by the rivet H. The shoulder h also provides against disengagement or compression. The shoes are alike at both ends.

All the parts except the rivets and sleeve are made of malleable cast-iron.

In the extension-braces heretofore in use a great difficulty has been encountered in placing them in position, from the fact that no provision was made for their engaging on the face of the shoe with the surface of the plank lining, and, further, that their construction provided for'only a limited angular adjustment, and that onlyin one plane, thus rendering them liable to slip out of place and from strain to gag the screw within the sleeve. The twisting strain caused by the friction of the nut also puts them out of order. I overcome all these difficulties by my improvements. The sharp edges a a a a on the face of the shoe obtain a firm hold on the plank lining K, Fig. 1, so that jar or misuse cannot affect it, while the ball-and-socket joint permits of radial adjustment and alignment of the working parts, no matter what angle the face of the shoe may have to assume on the roughplank lining. This does away with the gagging of the screw in the sleeve and reduces the labor of placing and removing the braces.

The lugs on the face of the ball will prevent any twisting motion when working the nut and consequent displacement of the parts.

I am aware that prior to my invention 6X tensible braces for excavations have been made with screw-stem, nut, sleeve, and shoes. I therefore do not claim such a combination,

broadly; but

What I do claim, and desire to secure by Letters Patent, is

1. In a brace of the character described, the combination of shoes having sockets provided with recesses, of two adjustable parts or sections having their outer ends fitting in said sockets and having lugs to engage the recesses thereof to prevent rotation of the movable or adjustable parts, substantially as described.

2. In a brace of the character described, the combination of the shoes having the sockets and recesses, the sleeve and screw carrying the balls having the lugs, and the nut engaging the screw.

3. In a brace of the character described, the

combination of the shoes having sockets provided with recesses, the two adjustable parts or members having balls at their outer ends fitting the sockets of the shoes and having lugs to engage the recesses thereof, and caps for securing the balls in the sockets of the shoes, substantially as described.

4. In a brace of the character described, the combination of the shoes having the recesses, the screw carrying a ball provided with lugs engaging the recesses of one of the shoes, the sleeve in which the screw travels, the ball secured to the sleeve, having lugs engaging the recesses of the other shoe, the caps for retaining the ballsin the shoes, and the nut engaging the screw.

In testimony whereof I affix my signature in presence of two witnesses.

WM. J. DUNN.

Witnesses:

CHAS. D. RAY, J. B. GEYsER. 

